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Zlin Aviation Outback Shock Cub

Those may be desser tires but they are not 31 inch Bushwheels.
For years, any front end loader around here was called a “pay loader.” That name stuck no matter who the manufacture was. Bushwheels are so popular, any big fat tire is getting the same quick logo, you know what they mean, however, may or may not be the “real Bushwheel”. Those ones look like Desser 31s” because that wheel is way bigger then a 6” rim. (Probably a 10” (?)
 
For years, any front end loader around here was called a “pay loader.” That name stuck no matter who the manufacture was. Bushwheels are so popular, any big fat tire is getting the same quick logo, you know what they mean, however, may or may not be the “real Bushwheel”. Those ones look like Desser 31s” because that wheel is way bigger then a 6” rim. (Probably a 10” (?)

31” Aero Classic’s on 10” Beringer rims powered by the 914 turbo spinning a 1.93M Kiev three blade propeller.
 
21 FEB 19 As an important update on pr we have been working with the Savage factory and are now offering the plane, including VHF radio and XPDR for $112,700USD. This price is limited and includes all shipping and registration. If you have any specific questions please contact me off line at my email address: bill@sportair.aero or our website www.savage.aero. Thanks, Fly Safe! Fly Fun! Bill
 
Just something to throw into the discussion. As a Shock Cub/Outback shock owner, I would generally (acknowledging my bias) lean toward the shock cub over the Ultra. The Outback Shock has a MTOW of 650kg (tested a little higher than that) and it's greatest appeal is its ruggedness and strength. When you look closely at the fuselage and landing gear, it is made for back country flying that contains the occasional mishap. The Ultra is made to be light (and to suit the European Ultra light standard) and has a MTOW of 600kg. Don't get me wrong, it is an awesome machine in it's own right, designed and built by the same people, but I think they each have a slightly different mission. The Ultra would probably land a little shorter, but seriously with the shock cub stalling out at 18knots indicated, I could never envisage needing to land any shorter than I do now. It feels like you touch down at a fast walk. Hope this helps. Cheers Damien
 
To the original post:

As a Rotax owner I would not touch that 915 for at least 5 years. Let the UAV guys work all the bugs out of them. When you get that many electronics, turbo, gear box, new MAP settings every week, etc., all in one place, in all kinds of different airframes each with their own quirks, cooling issues, etc., there’s going to be a steep curve.

But that’s just me. Just not that adventurous here in the land of tires over very cold water. To each their own.

On a 650# airframe that’s cub-like, I’d wonder what structure has been sacrificed to get there. Also, that sumbitch is gonna ride rougher than a cob in the turbulence. The 752# S7S is about the top of my threshold for pain in that regard.

Again, maybe I’m just getting old[emoji1]
 
The reference to 650 and 600 in this thread are concerning Kilograms, not pounds. That's 1430 and 1320 pounds, respectively.
 
The reference to 650 and 600 in this thread are concerning Kilograms, not pounds. That's 1430 and 1320 pounds, respectively.

The OP I read states “The 912ULS version weighed in at 660 lbs. empty...” in the third to the last paragraph. That’s all I know.
 
To the original post:

As a Rotax owner I would not touch that 915 for at least 5 years. Let the UAV guys work all the bugs out of them. When you get that many electronics, turbo, gear box, new MAP settings every week, etc., all in one place, in all kinds of different airframes each with their own quirks, cooling issues, etc., there’s going to be a steep curve.

But that’s just me. Just not that adventurous here in the land of tires over very cold water. To each their own.

On a 650# airframe that’s cub-like, I’d wonder what structure has been sacrificed to get there. Also, that sumbitch is gonna ride rougher than a cob in the turbulence. The 752# S7S is about the top of my threshold for pain in that regard.

Again, maybe I’m just getting old[emoji1]

I own a short tail S-7 and am in 100% agreement with everything you are saying! I looked at the engine at Oshkosh and being an old hot rodder, that engine is a nightmare with all the electronics, boxes, lines, etc. Sure wouldn't want to have an issue somewhere off the beaten path. I already have issues with trying to find someone local that can diagnos issues with my current Rotax 912. Having just removed the engine to get at the ignition/stator assembly is more involved than it should be. I could only imagine the nightmare if one had an issue with the 915!!

Also have the same feelings about turbulence and these light wing loaded airplanes. I have had plenty of experience of battling severe turbulence in it and if it isn't fairly decent weather, I'll take the good old 172! The S-7 can be quite a bucking bronco in turbulant conditions. I'm getting too old for it also!! It is a blast the rest of the time!!
 
It's all relevant, coming up from ultralights, I'm always pleased the way my S7-S handles the bumps! I'm sure a Citation X pilot would have a different opinion. An inescapable aspect of the great low speed handling, and not doing it with gobs of horsepower but doing it with the wing. Nothing unusual about the S-7 in this respect, a Kitfox may be a bit different but guess what, it has a smaller wing and doesn't land as short or slow as the 7. I don't recall my T-Craft being much different in bumps, any light wing loaded plane will be effected more, but I just relaz and go with it, kinda fun.....and I have plenty of control authority. My Prius handles and feels differently then my 1 ton flatbed, same deal. 15 MPG versus 55 MPG though. Airplane wise, I consider it the price I pay for sub 4 GPM burn rates and the ability to land anywhere, and takeoff again. But right now I'm sitting on my ass at my desk, ask me again after crawling out of the plane all beat up, my attitude may differ.
 
I own a short tail S-7 and am in 100% agreement with everything you are saying! I looked at the engine at Oshkosh and being an old hot rodder, that engine is a nightmare with all the electronics, boxes, lines, etc. Sure wouldn't want to have an issue somewhere off the beaten path. I already have issues with trying to find someone local that can diagnos issues with my current Rotax 912. Having just removed the engine to get at the ignition/stator assembly is more involved than it should be. I could only imagine the nightmare if one had an issue with the 915!!

This is pretty funny timing as a couple of days ago I would have strongly disagreed with both of y’all because of my fascination with the latest and greatest. I’ve been obsessed with the 915 iS for the past year and finally had my chance to get behind it and operate the beast at full tilt. I flew the engine behind the new Sling TSi and was impressed as that engine has turned this airplane into a monster.

The first flight I rode in the back and was amazed at how powerful the engine was taking three of us adults, 40 gallons of fuel, and a ton of stuff in the back at over 1200 FPM doing 90 knots. This airplane was running the Airmaster constant speed hub behind a 72” three blade Airmaster prop. After easily climbing to 7,500ft my buddy and I saw true airspeed over 150 knots burning 6.7 GPH which was really impressive.

When we got back and landed I got to try the airplane out and get a good sense for the engine. On our way back, wouldn’t you know it, Lane B lights up. After the demo pilot tried recycling the lane a few times both Lane A and Lane B lit up. My first thought was, “Really Rotax?” We were on a long final over a never ending sea of houses so I climbed and made sure we came in a bit high just in case. The lights eventually went off but I left that day disappointed and was hoping after 7 years of the 912 iS they’d have these issues wrapped up.

A few more impressions of the 914 vs 915.

The 914 starts smoother, the 915 really kicks and judders when you start it. There’s a lot more to do to get the 915 ready to start as well. After you pushed a bunch of switches you have to keep the throttle at half for cold starts which is unnerving.

There was no apparent difference in smoothness between either engine. Throttle response is the same on both. But, the 915 is a monster! It is extremely powerful and should turn the Shock Cub into an amazing performer, but after that flight, I think my favorite Rotax is still the 914 until they fix their lane issues. Who knows how long that’ll be! I came away a bit let down in the end and definitely agree it needs time to mature.

I really think SportairUSA will have a winner in the Shock Ultra and 914 combo. From studying the landings of both models I think there’s more angle of attack to work with and it should just be a stellar performer for the backcountry.
 
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Looks like a test flight any day now.
 

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Love the plane. Just shows due to the uniqueness of the design, there ain’t no end to the iterations of Mr Pipers little mount.
 
I like that flip up cowl, great access. Can't tell from the pics, but it looks like maybe a big gap between the inboard section of flap and fuselage, when not deployed? That's easy enough to close up with a simple sheet metal piece, I did on my bird, otherwise lots of air spilling thru there. Great video!

Not lusting after that motor yet though, nor are most guys I know flying behind the stock (though with some mods, so not stock I guess!) 912S engine, weight and complexity being the main reason. The "jury" is still out by and large. Then again, I'm not even interested in a 914, the turbo version of the 912 that's been around for quite a while, for the same reasons, weight and more stuff, guess I'm just a weight weenie.
 
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Possibly a winning combo for STOL ops! The 912 powered STOL planes were losers at the Paradise Field this year.
The Titan powered SuperStol XL and the blue and white cub followed by the camo Aircam were the winners in short take offs, sustained steep climb outs and short landings. Zlin is zeroed in on a serious STOL contender with this Shock Cub 915is combo. They know a 912 powered machine can’t compete in ultimate STOL.
 
I'm with Simkot! While it's an amazing engine, I have little interest in it. I recently visited with a Rotax guru that has one on a RANS S7. The owner likes the performance, but it comes with an approximate 100lb. weight gain to the aircraft. What I didn't like was the 'rats nest' and complexity under the cowl. Looks like what one sees upon opening the hood of any new vehicle. Being in the boonies, and having any issues, well, hope you have a buddy to fly you out.
 
Just clarifying that the Aircam is powered by not one, but two 912 engines. And it performs beautifully.
 
I'm with Simkot! While it's an amazing engine, I have little interest in it. I recently visited with a Rotax guru that has one on a RANS S7. The owner likes the performance, but it comes with an approximate 100lb. weight gain to the aircraft. What I didn't like was the 'rats nest' and complexity under the cowl. Looks like what one sees upon opening the hood of any new vehicle. Being in the boonies, and having any issues, well, hope you have a buddy to fly you out.
Yep. Heard those statements so many times it becomes like “yeah whatever”. Lol. Not many new cars busted on the side of the road with the hood up cause there’s a big issues in the “ rats nest “. “Oh but it 100 lbs heavier”. Yep it’s a factor but don’t shut your eyes completely....take a peek at the STOL planes actually performing really well, in all fronts, including fuel burn. And the ones performing really well? Those ones with Titan 180s for example. The lighter 912 powered planes are being eaten alive.
Back to “complicated modern engines”. Perhaps a K Car would be a good seller now? Like it’s just so simple you could just “wrench er on the side of the road and motor on. Surprising that Toyota and Honda have any sales at all given complicated unreliable thing under the hood lol.
I have a RANS S-7S. With a 912.
 
60F73E8A-D889-4AEF-82EC-B8EDC09B093B.jpegI’m a big fan of the 915 iS, and believe it will become the engine that the LSA and experimental market look to. After having flown behind it with the Sling TSi, I can say that it is extremely powerful even with three people on board. The Airplane Factory is seeing 166 knots true at altitude burning 7.4 GPH. Awesome right there!

This combination of engine and airframe is about the ultimate STOL setup right now. I had a chance to fly the Titan Outback Shock about a month ago and my oh my was the climbout deck angle and gear just unbelievable. The breakout forces were a bit firmer than I would have liked, but the aircraft has wonderful control at extremely slow air speeds. It’s just a heavier feel and surprised me in that way. I kept thinking to myself how much better the Shock would be with a 100 lbs shaved off the nose and lot quieter and smoother engine running the show.

Here are are some photos from the AERO Show today. An all black 915 Shock Cub and an all aluminum concept wing which could yield cruise of 100kts with slow flight maintaining 20kts. Exciting stuff!
 

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Cool wing, love the flaps. It looks to have the SLOW part handled, 100 knots? With that engine pulling it, even with that draggy gear, probably, along with a fuel burn similar to the Sling. Whether that's a high or low burn depends on what you're used to! Pulled back a bit, it should offer similar economy to a regular 912 though.

I see Ronnie Smith, Rotax engine guru and expert, has stuffed one into a RANS S-7S, a pretty good trick, while keeping what seems to be the same cowl. He also added two extra wing tanks, and reported a fuel burn of mostly 6+ GPH on a flight to Alaska and back.
 
Cool wing, love the flaps. It looks to have the SLOW part handled, 100 knots? With that engine pulling it, even with that draggy gear, probably, along with a fuel burn similar to the Sling. Whether that's a high or low burn depends on what you're used to! Pulled back a bit, it should offer similar economy to a regular 912 though.

I see Ronnie Smith, Rotax engine guru and expert, has stuffed one into a RANS S-7S, a pretty good trick, while keeping what seems to be the same cowl. He also added two extra wing tanks, and reported a fuel burn of mostly 6+ GPH on a flight to Alaska and back.

Yeah! I talked to Ronnie about it and he seemed very happy with the setup. I agree, extremely impressive he was able to fit that engine in such a tight space. Seems the fuel burn is less than a 912 ULS and 914 UL pulled back.

https://youtu.be/CUwa4_GHrpU
 
Last time it was sodium valve stems and now a new mandatory service bulletin having to do with the heat shield on the turbo. That is sort of my concern with installation in tandem planes (tight, narrow cowls), keeping all that heat away from where it should be kept away from. That would be a lot easier in side by sides with a wider cowl. I have nothing against the engine and anything new will have a few bugs along the way but I sure get a lot of bulletins in my inbox (I went to the inspection school for rotax so they have my email).
 
I was just down visiting Ronnie. Super guy! Brought my engine down to get some ignition things checked. Had a look at his S7 with the 915, took a couple of photos. I'll just say this, gave me a headache just looking at the complexity! He's a genius for getting it all to fit into the confines of the S7 cowl!
 
I was just down visiting Ronnie. Super guy! Brought my engine down to get some ignition things checked. Had a look at his S7 with the 915, took a couple of photos. I'll just say this, gave me a headache just looking at the complexity! He's a genius for getting it all to fit into the confines of the S7 cowl!
What happened to you’re ignitions?
 
Internal breaks in the wires. I had fixed it several years ago and I think the vibration just caused it to break in another spot further down the wiring loom. It was inside the braided section.
 
Just come across this thread. Am a new Zlin Shock Cub owner. Waited ages (over a year) for the 915 and finally went for the 914; very satisfied with the decision. Desser Aero Classic 31” (more like 29”) on Beringer 10” rims and a fat Matco tail-wheel. Really enjoying it. We did have and continue to have teething issues but are working through them. General build quality is excellent but Zlin really should have picked up more of the niggles before it left the factory.

We had significant engine over-heating issues as soon as we started flying her. The oil-cooler radiator was 50% blanked by the cowling and oil temperatures were way too high. The local agent’s engineering shop did a great job of modding the cowl which resolved that issue. CHT’s were way too high - the plumbing to the 2 engine radiators was not at all great - ported to the two radiators through a T-piece junction which resulted in very unfavorable fluid dynamics. The local engineers re-plumbed the coolant, routing the total flow through one and then the other radiator. Simply put, once this was done all engine cooling issues were over.

Other, currently unresolved issues still in the process of being resolved are:

* The rear control stick impacts the forward seat to the extent that forward elevator travel is restricted by almost 2 inches. I’ve removed the rear stick (it has a quick-disconnect) as it really was unsafe. Working on a replacement stick with enough bend to avoid conflict with the front seat.

* The Beringer brakes are just not ‘grabby’ enough. I’ve wound the adjustment knob to the maximum and they’re still well below where they need to be. The brakes hold the aircraft against power but just barely and are ineffective for proper ground maneuvering, especially in a crosswind.

* I’ve never been able to select the third (full) notch of flap in flight. It goes to the notch on the ground, with no aerodynamic load. The flap attachment arm is striking the fuselage panels on either side on the way to the fully extended position. The factory insists they got full flap during testing but I simply don’t understand how that was possible. We’re going to cut a section out of the fuselage panels which the arm passes through and that should resolve this issue.

I really do feel the above 3 issues should have been identified and resolved during testing at the factory.

Nonetheless it is a fantastic machine; the 914 is a great compromise between a reliable, well known power-plant, weight, cost and fuel-efficiency (averages around 20 litres/ just over 5 USG per hour). We’re still exploring the envelope, stall is docile and a non-event, occurs well under 20 knots (with just the 2nd notch of flap) and results in a rate of descent around 600 feet per minute, power-off, stick fully back, no wing-drop. Application of sufficient engine power reduces the rate of descent. No doubt she’ll land in the hover with around 20 knots of headwind. Still building courage and experience before we go there.

Here’s a snapshot - https://www.facebook.com/562437460/posts/10156024979342461?s=562437460&sfns=mo
 
G’day, we solved the rear stick problem by moving the front seat to the more forward position (well it sort of solved it, it’s better). We have Berringer dual calipers with 6 inch and 26 inch abw and they are great, we decided not to install the anti skid as it seems to take away feel.

Hope this helps. cheers Damien
 
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* The rear control stick impacts the forward seat to the extent that forward elevator travel is restricted by almost 2 inches. I’ve removed the rear stick (it has a quick-disconnect) as it really was unsafe. Working on a replacement stick with enough bend to avoid conflict with the front seat.

* The Beringer brakes are just not ‘grabby’ enough. I’ve wound the adjustment knob to the maximum and they’re still well below where they need to be. The brakes hold the aircraft against power but just barely and are ineffective for proper ground maneuvering, especially in a crosswind.

* I’ve never been able to select the third (full) notch of flap in flight. It goes to the notch on the ground, with no aerodynamic load. The flap attachment arm is striking the fuselage panels on either side on the way to the fully extended position. The factory insists they got full flap during testing but I simply don’t understand how that was possible. We’re going to cut a section out of the fuselage panels which the arm passes through and that should resolve this issue.

I really do feel the above 3 issues should have been identified and resolved during testing at the factory.

No kidding?

Brakes- you need to run in the pads prior to effective. Get them hot as heck and let them cool off, should work better.

Rear stick- bend aft a bit. Moving the front seat is NOT a good solution, some time in a long flight you decide to push the seat back for a stretch and bad may happen.

Flap hangar not allowing movement? that is a factory issue, or installation problem. Good luck!
 
Rear stick- bend aft a bit. Moving the front seat is NOT a good solution, some time in a long flight you decide to push the seat back for a stretch and bad may happen.

Just for info, the shock cub does not have a flight movable front seat. Just two bolt positions set up prior to flight. But as you say, bending will do the trick.
 
I wouldn't call over 5 GPH with a Rotax a low fuel burn! I fly my S-7S all over the west with a non turbo 912S (but with a BigBore Zipper mod) from my field elevation of 5640' and always average less then 4, usually less then 3.5. It climbs at 350 fpm at 13K, (in the winter anyway) all with no turbo heat and complexity not to mention the extra weight. You couldn't give me a turbo, seems like most of the guys who think they need them, live low.
 
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